Many of our teams missed a meeting in the past 2 weeks, so I’ve combined the posts for the weeks.

Oakwood is starting off the school year with new and excited members of the Solar Army! Previously, Oakwood manufactured a UV-ozone cleaner to ultra-clean the FTO glass, making it very hydrophilic. Hydrophilic surfaces allow water to spread evenly instead of forming a droplet. Using a piece of plastic with holes where the spots would eventually be, the UV-ozone treatment allows for perfect placement of our drops while pipetting. This procedure allowed aqueous solutions to dry uniformly on the surface, so the spots don’t have a coffee ring effect. Several other teams are planning on building their own ozone cleaners this year based on Oakwood’s design.

This fall Oakwood is going to make a new template meant for the smaller size glass that SEAL uses. The previous template was for slightly larger glass, and the plastic didn’t hold up well to continued UV-ozone treatment. They are going to try some more stable plastic pieces and see if those are better. They are also going to test how salts of the same metal, but with different counter-ions and non-metal additives, might produce different film properties. They will start by looking at simple iron salts which are readily available.

Concordia group reviewed the conceptual basics of water-splitting catalysts. Their mentor, Dr. Kenny,  also described how H2O splitting is similar to photosynthesis/glycolysis in nature. They discussed how metal oxides act as catalysts when splitting H2O, and how acids and bases affect water half-splitting reactions, which result in hydroxides that will be split into water, oxygen, and electrons. If you have any questions about these concepts, ask the Concordia team in the comments section!

Poly is still continuing ahead with work on bismuth nitrate, and PCC is making solutions of bismuth(III) nitrate, lead(II) nitrate, aluminum(III) nitrate, and nickel(II) nitrate based on results of some plates they tested last week. Mayfield’s SEA team is testing combinations of Co and Cu with Al and Zn. RAM team is testing BiCoW combinations since their BiVW plate did not perform well (though their vanadium solution had precipitated out and turned yellow, so it may be a problem with their vanadium). 

The San Marino Red Team continued experimentation with Juice from Juice, testing figs, blackberries, blueberries, and green beans as dyes. After assembling the cells, the blue berry dye worked the best (that’s a surprise to me- blackberries usually are better)! They also plan to test spinach leaf extract an raspberries in the future as well as testing if increased surface area of the DSSC affects their results. Red Team also made a plate with various combinations of copper sulfate, nickel nitrate and manganese chloride. San Marino’s Magic Wand Team examined their plate from last time and noticed that a few spots had turned a dark color which they decided was indicative of a solid result. Those spots consisted of the ratios 3:3:4 and 7:1:2 NaH2PO2: KH2PO4: NiCl2. They made another plate that consisted of just these two ratios. Plans to compare dropcasting to electrodeposition for the two materials is put on hold as the “magic wand” for electrodeposition is broken. All the samples were dropcasted this time. The team also talked about semiconductors and band gaps and our hoping these materials they spotted will be metal oxides with a band gap in the “sweet spot” for water oxidation.